Decision theory analysis of response latencies in vigilance

In 2 separate experiments with 30 males, the latencies associated with all 4 categories of response (correct detections, false alarms, correct rejections, and omissions) were recorded during the performance of a 45-min visual monitoring task. In Exp I, concerned primarily with criterion changes in vigilance, signal probability was manipulated. Exp II was concerned with sensitivity changes resulting from changes in event rate. In the 1st experiment, latencies associated with correct detections and false alarms increased, whereas those associated with correct rejections and omission errors decreased, with an increase in criterion. In the 2nd experiment, a reduction in sensitivity associated with an increased event rate exerted significant and opposing effects on latencies of responses to signals (correct detections and omissions) while leaving the latencies of responses to nonsignals (correct rejections and false alarms) unchanged. In both experiments, it was observed that while the latencies associated with positive responses increased with time on task, the latencies of negative responses decreased with time. These results are consistent with the predictions of a decision theory model for response latency extended from signal detection theory, which assumes an inverse relation between response latency and distance from the criterion. (37 ref)